The registry, which is the largest survey in American history to track the health effects of a disaster, is aiming to get a better picture of how living through two major tragedies can affect both physical and mental health, said Michael Farfel, director of the WTC Registry, at a Community Board 1 meeting Thursday.

"I think this will be an important survey," Farfel said. "We're hoping many people will participate."

For the pilot survey, the registry is targeting about 4,500 9/11 survivors who live in areas flooded by Sandy and another 4,500 who were on higher ground.

They hope to launch the survey, which will ask questions about mental illnesses including post-traumatic stress disorder, as well as physical ailments, in the first week of April.

The WTC Registry has more than 70,000 members, including more than 11,300 people who lived south of Canal Street on Sept. 11, 2001, and looks at the health effects on specific groups of people, including young children.

For more information about the World Trade Center Health Registry's survey, visit the website or call 866-692-9827. To learn about free medical treatment for residents with 9/11-related conditions, call 888-982-4748.

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